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Late Maastrichtian foraminiferids and diatoms from the Polish Carpathians (Ropianka Formation, Skole Nappe): a case study from the Chmielnik-Grabówka composite section

Gasiński M. A., Olshtynska A., Uchman A.

Acta Geologica Polonica

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2013

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Vol. 63, no. 4

515--525

EN

Well-preserved foraminiferids have been found in the Chmielnik-Grabówka section (Skole Nappe, Polish Carpathians). The Abathomphalus mayaroensis (late Maastrichtian) and Racemiguembelina fructicosa (earlylate Maastrichtian) standard planktonic foraminiferal biozones have been recognized, based on the occurrence of their respective index species. Sediments of the R. fructicosa Zone contain diatoms, which are a rare component of Cretaceous flysch microfossil assemblages in the Carpathians. The diatom frustules and some foraminiferid tests are pyritized, probably after burial in the sediment, below the redox boundary or in the oxygen-deficient microenvironment inside the frustules or tests of microfossils; the presence of trace fossils and bioturbational structures in the same bed indicate an oxygenated sea floor.

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The Trawne Member (Albian-Cenomanian, Pieniny Klippen Belt, Carpathians) : a new insight into its foraminiferal assemblages and biostratigraphy

Pióro K.

Studia Geologica Polonica

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2005

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Vol. 124

237-248

EN

Detailed micropalaeontological analysis of samples from the Pasieczny and Trawne stream sections has been undertaken. Twenty five species including seventeen planktonic taxa have been identified. The Rotalipora ticinensis - Planomalina praebuxtorfi new biozone has been proposed. In the Pasieczny Stream section, turbiditic sedimentation commenced during the Early Cenomanian (Rotalipora appenninica Zone). The new biozone R. greenhornensis has been established. The Rotalipora reicheli - Rotalipora greenhornensis Zone, based on coexistence of both nominal species was recognized. The studied foraminiferal associations have confirmed palaeobathymetrical associa- tions B1-B2 (middle part of the continental slope).

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A Middle Cenomanian foraminiferal assemblage from the Nowe Rybie section (Żegocina Tectonic Window, Subsilesian Unit, Polish Outer Carpathians)

Machaniec E., Gasiński M. A., Ślączka A., Leśniak T.

Studia Geologica Polonica

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2005

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Vol. 124

249-258

EN

The Żegocina Tectonic Window is the most eastward located tectonic window of the Lanckorona-Żegocina Zone in the Polish Outer Carpathians and represents the slope parts of the Silesian basin and intrabasinal uplifted zones of the Subsilesian Unit. Upper Cretaceous and Palaeocene variegated marls, typical deposits of the studied part of the basin, are intercalated with the so-called Rybie beds (local sediments of siliciclastic submarine fans). A Middle Cenomanian foraminiferal assemblage (Rotalipora reicheli Zone) is here described from these sediments. The assemblage contains numerous planktonic (epipelagic and bathypelagic) foraminiferids, which is rather unique within the "Flysch" type assemblages. A middle slope palaeodepth is suggested as the depositional environment, based on benthic and planktonic foraminiferal associations.

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Cretaceous-Paleogene boundary problem in Libya: the occurrence of the foraminiferal species Abathomphalus mayaroensis (Bolli) in the Western Sirt Basin

Tshakreen S. O., Gasiński M. A.

Geological Quarterly

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2004

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Vol. 48, No 1

77-82

EN

The position of the K/P boundary in wells in the Western Sirt Basin of Libya is problematic. The biostratigraphic definition of the K/P boundary in the subsurface is based on the extinction of the eponymous taxon of the standard latest Maastrichtian foraminiferal Abathomphalus mayaroensis Zone. We have unambiguously recognised this taxon from the Sirt Basin subsurface sections for the first time. All the latest Maastrichtian foraminiferal assemblages are dominated by planktonic foraminiferids. Some of specimens are pyritised, indicating organic flux to the basin floor, causing oxygen deficiency in the depositional environment. The occurrence of characteristic bathypelagic and some epipelagic species indicates that the environment of deposition is outer shelf–middle continental slope.

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Biostratigraphy and Palaeoenvironmental Analysis of the Żegocina Marls in the Żegocina Tectonic Window (Subsilesian Unit, Polish Outer Carpathians)

Gasiński M., Leśniak T., Wróbel A.

Bulletin of the Polish Academy of Sciences. Earth Sciences

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2003

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Vol. 51, nr 1

1-9

EN

The Żegocina siliceous marls contain well preserved and diversified foraminiferal assemblages dated as late Early Campanian - Early Maastrichtian (from G. ventricosa to G.gansseri standard zones). Based on qualitative and quantitative analyses of foraminiferal assemblages, external shelf - upper slope have been suggested as the deposition palaeodepths of the studied marls.

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Latest Maastrichtian Foraminiferal Abathomphalus mayaroensis Zone in the Subsilesian Unit (Polish Outer Carpathians)

Gasiński M., Leśniak T., Piotrowski M.

Bulletin of the Polish Academy of Sciences. Earth Sciences

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2001

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Vol. 49, nr 2

89-97

EN

Maastrichtian standard zones: Globotruncanella havanensis, Globotruncana aegyptiaca, Gansserina gansseri and Abathomphalus mayaroensis have been recognized within the Rybie beds of the Subsilesian unit, Polish Carpathians, based on planktonic foraminiferids. The latest zone; and the presence of its index form, are very rarely recognized in the Polish Outer (Flysch) Carpathians. Foraminiferal assemblages of the Abathomphalus mayaroensis Zone of the Rybie beds contain very differentiated planktonic, calcareous and agglutinated benthic taxa. Qualitative, quantitative and "morphogroup" analyses of the microfauna helped reconstruction of depositional environment and bathymetric conditions of the Rybie beds.

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Biostratigraphy and Palaeoecology of the Late Cretaceous Foraminiferids at Krzyworzeka Stream Section (Subsilesian Unit, Polish Outer Carpathians)

Machaniec E., Gasiński M., Leśniak T.

Bulletin of the Polish Academy of Sciences. Earth Sciences

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2001

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Vol. 49, nr 2

99-107

EN

Assemblages of foraminiferids from the Upper Cretaceous section of the Subsilesian unit (Polish Outer Carpathians) have been analyzed. The age of the studied samples bas been estimated as Turonian-Campanian, based on agglutinated as well as planktonic foraminiferids. Morphogroup analysis of the studied foraminiferids showed an increase of the organic flux on the basin floor.